Multi-chambered fluid-fillable apparatus

ABSTRACT

The invention relates to a multi-chambered, fluid-fillable apparatus apparatus, comprising two sheets bonded together to define a plurality of cells between them. In a first aspect, at least one, and preferably both, of the sheets are formed from polyvinyl alcohol. In a second aspect, the sheets are sealed together using both permanent and non-permanent seals. The non-permanent seals are formed to rupture at a predetermined internal pressure in order to dissipate externally applied load.

FIELD OF THE INVENTION

The present invention relates to a multi-chambered fluid-fillableapparatus, and method of manufacture of such an apparatus, suitable fora variety of applications where protection and shock absorption isrequired. The invention is primarily described in relation to protectivepackaging, but this is just one possible application of the invention.

BACKGROUND TO THE INVENTION

There are many types of inflatable, protective packaging available.These range from pre-inflated bubble films to an extensive range ofinflatable on-demand systems, which rely on machinery to inflate simplevoid fill bags or more sophisticated cushioning products. Other types ofprotective packaging include loose fill, profiled foam, vermiculite andpostal products known as “Jiffy Bags”.

This list of packaging products is not exhaustive, but almost allexisting protective packaging solutions suffer from a common problem,which this invention seeks to address. Prior packaging solutions arelargely made from petroleum based materials or composite materials andare difficult to dispose of in a satisfactory manner.

It is estimated that 56% of all packaging waste is protective packagingwaste. With land fill resources diminishing and other environmentalconcerns, the drive for an environmentally responsible packagingsolution has never been greater. While much of the petroleum basedpackaging can be recycled, it needs to be sorted from other wastematerial, and the costs involved are often prohibitive.

In recent years that has been a push to use biodegradable plastics forprotective packaging. There are two principal types of biodegradableplastics; one uses a small proportion of non-oil based material, such ascorn starch, the other uses photo-degradable material that breaks downwhen exposed to sunlight.

Unfortunately, there are a number of problems with these biodegradableplastics. One problem is that they will only degrade under specificconditions. Starch based plastics need digesters to break them up in thecomposting process, otherwise they will not degrade. Photo-degradableplastics clearly need light and so will not degrade in land fill sites.

Furthermore, the mixture of degradable and non-degradable plasticscomplicates plastics sorting systems and is a significant cost.

So, while the use of biodegradable plastics has been recognised as asolution to the waste problem, it is now recognise that currentmaterials will only be viable when there is a corresponding, completecomposting infrastructure in place.

There are also performance issues with these biodegradable plastics. Thestrength and barrier properties of biodegradable plastics in use forpackaging are inadequate for some applications.

A further problem with existing inflated packaging is that the inflatedcells will rupture at a predetermined load, resulting in an abrupt lossof cushioning. It would be desirable to be able to provide for a moregradual dissipation of load and a reduced susceptibility to rupture.

Accordingly, there is a need for an environmentally friendly protectivepackaging solution with improved cushioning and barrier performance.

SUMMARY OF THE INVENTION

The invention is defined in the appended claims to which referenceshould now be made.

Aspects of the present invention provide significant advantages. All ofthe physical properties of polyvinyl alcohol film are beneficial ininflatable packaging. It is water soluble and biodegradable, thus easilyand safely disposed of. It has greater elasticity and tensile strengththan conventionally used materials; it has excellent barrier propertiesfor oils, odours and oxygen. It has an affinity to itself, and it istransparent, electrically dissipative and non-toxic.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will now be described in detailwith reference to the accompanying drawings, in which:

FIG. 1a is plan view of an example cushioning apparatus in accordancewith the present invention;

FIG. 1b is a cross-section of the apparatus of FIG. 1;

FIG. 2 is a cross-section of a further example of an apparatus inaccordance with the invention;

FIG. 3 illustrates an adhesive sealing patch forming part of anapparatus in accordance with the invention

FIG. 4 illustrates the use of sacrificial seals in accordance with anexample the present invention;

FIG. 5 illustrates a further example of the position of sacrificialseals in an apparatus in accordance with the present invention;

FIG. 6 illustrates a process for producing a cushioning apparatus inaccordance with the present invention; and

FIG. 7 illustrates an apparatus in accordance with the invention,suitable for use in a method of forming individual fluid filledpackages.

DETAILED DESCRIPTION

FIGS. 1a and 1b illustrate an example of an apparatus in accordance withthe present invention. The apparatus shown in FIGS. 1a and 1b comprisestwo sheets of polyvinyl alcohol (PVOH) film bonded to one another toprovide a plurality of inflatable (or already inflated) cells betweenthem. As shown, upper sheet 10 is bonded to lower sheet 11 with aperipheral seal 12 around the circumference of each sheet. The upper andlower sheet may be formed from a single web of PVOH, so that on oneside, instead of a permanent seal, there is simply be a fold line.Further bonds 13 are made between top sheet 10 and bottom sheet 11 in aninterior region to define a plurality of interconnected cells. An inputport 14 is provided, in a gap in the peripheral seal 12, in order toallow the cells to be inflated to provide a cushioning apparatus (orfilled with another fluid or a powder). Once the cells have beeninflated, the input support 14 can be sealed, as shown in FIG. 1b , sothat the cells remain in an inflated condition.

The key aspect of the present invention is the use of polyvinyl alcoholfilm. In the example of FIGS. 1a and 1b , both upper sheet 10 and lowersheet 11 are formed from polyvinyl alcohol film. Polyvinyl alcoholoffers a number of advantages. A key advantage is that PVOH is watersoluble, breaking down into a carbon dioxide and water. PVOH film isalso odourless and non-toxic. It has high tensile strength,extensibility, elasticity and flexibility as well providing high oxygenand aroma barrier properties. PVOH also has electrostatic dissipativeproperties, making it suitable for the packaging of electrical goods,and is an oil and grease barrier.

PVOH has been used for packaging goods, such as detergent for use inwashing machines, where the water soluble properties of PVOH allow thedetergent to be released during a wash cycle. PVOH has also been used inthe packaging of certain chemicals, such as pesticides. However, PVOHhas not been used in the production of inflatable or pre-inflatedcushioning. However, as well as being biodegradable, the tensilestrength and extensibility of PVOH make it an excellent material formaking shock absorbing, inflated cushions having superior performance toexisting cushioning products.

PVOH film is readily available from a number of manufacturers, in arange of grades, thicknesses and degrees of hydrolysation. Preferably,the PVOH sheets are made using the cast method, as this gives rise tomore uniform and consistent films than the blown or extruded films. ThePVOH films may be partly or fully alcoholised or hydrolysed. Preferablythe PVOH film is formed from polyvinyl acetate film alcoholised orhydrolysed between 40% and 99%, and preferably between 70% and 90%.Details of the the manufacture of PVOH film can be found in “Packagingof Pesticides and Potentially Hazardous chemicals for Consumer Use” byDavid Edwards, PIRA INTERNATIONAL, 1996.

The PVOH film may be unoriented, mono-axially oriented or bi-axiallyoriented. Warm water grades (i.e. film soluble only in warm water) aredesirable for some applications where water splash could be an issue.The maximum tensile strength of the material of the PVOH film ispreferably at least 20, more preferably from 30 to 80, N/mm ² and may beas much as 200N/mm ² or more; and the elongation at break is preferably200 to 380%, more preferably from 220 to 350%. Testing for these valuesis generally carried out at 23° C. and 50% relative humidity. Thethickness of the film is preferably between 10 to 500 microns, and morepreferably between 20 to 100 microns. For example, Aicello chemicalcompanies produce a number of grades of SOLUBLON™ PVOH films which canbe soluble in hot water or cold water. Thicknesses of around 40 TO 70microns would be suitable for a cushioning apparatus in accordance withthe present invention.

The PVOH film can be manufactured to hold relatively low water content.This film will act as a desiccant, making it particularly suitable forpackaging items that require protection from moisture.

It is within the scope of the present invention to provide a cushioningapparatus having only a single layer of PVOH film bonded to anothersheet of material, with the cells defined between them. Preferably, theother sheet of material is biodegradable, such as cardboard. The othermaterial may be water soluble or water insoluble and may be rigid orflexible.

The PVOH film or films may be laminated with other materials (againpreferably biodegradable materials) or laminated to further layers ofPVOH. There are a number of advantages to laminated layers of PVOH film,for example the elimination of any risk of pinholes in the film. FIG. 2shows a cross section of an apparatus of the type shown in FIG. 1,wherein the upper layer 20, comprises laminated layers of PVOH and thelower 21 layer comprises a rigid board.

PVOH films may be sealed to one another or to other materials using anumber of different techniques. For example, PVOH films may be sealedusing radio frequency welding (dielectric welding), ultrasonic welding,direct thermal sealing, induction sealing, induction welding, hot wireor hot plate sealing, and impulse sealing.

However, those conventional methods of sealing PVOH films are dependenton a number of critical parameters which include humidity, andtemperature, pressure and dwell time. Failure in the optimisation of anyof these parameters can very easily result in a compromised seal. Thishas been a problem for many years in the industry. Furthermore with themethods of sealing described above, controlling the humidity is anexpensive operation and is time consuming. A difference of plus or minusfifteen percent humidity can start to affect the seal parameters quitesignificantly. It is also important to understand that the manufacturingprocess of PVOH film either by the cast method or blown method requirescritical control of the humidity.

PVOH films may also be sealed to one another using adhesive. In apreferred embodiment of the invention, a fully water soluble andbiodegradable adhesive is used. The adhesive is applied to the watersoluble film using the gravure printing process. Appling a water solubleadhesive to the film during the film's manufacturing process is highlydesirable because the set up of the lines of cast PVOH film wouldalready have gravure or other methods of printing on line. Suchtechnology is used to laminate two layers of PVOH film. This method ofproducing the seals or matrix of seals has many advantages over theother methods, such as welding. During the cast manufacturing process ofPVOH the film is often printed in water soluble or dispersible inksusing gravure, flexo or even ink jet printing. All of these processesare capable of accurately putting down an accurate coat of ink and wouldbe equally effective in putting down a pattern of welds/seals using aspecially formulated water soluble adhesive. During the manufacturingprocess of the film a second layer of film is often bonded to anotherlayer to produce a laminated film and this process can be utilised inthe production of the present invention, to provide a finishedcushioning product as an integral part of the films' manufacturingprocess. Utilising such technology would save a considerable amount ofcapital expenditure, as most of the overheads are already paid for toproduce the film during its manufacture. A further benefit of usingadhesive is that, unlike heat sealing, it does not deform or thin thefilm and so does not weaken the film at any point.

Turning now to the particular embodiment shown in FIG. 1a , it can beseen that the cushioning apparatus comprises a plurality ofinterconnected inflated or inflatable cells. Having the cells in fluidcommunication with one another provides a number of advantages. Firstly,the cushioning apparatus can be transported in an uninflated state andthen simply inflated onsite using a single, or a few, sealable entryports. The apparatus can also be deflated after use and will return to aplanar configuration for storage before re-use. A second advantage ofhaving the cells in fluid communication with one another is the gradualdissipation of shock. In inflated cushioning such as bubble wrap, whereeach of the inflated cells is isolated from the others, there is aparticular internal pressure at which each isolated cell ruptures. Byproviding interconnection between each of the inflated cells, greaterlocalised impacts can be withstood because the increase in internalpressure is borne by all of the interconnected cells. The use ofmultiple cells rather than a single, larger cavity allows for moregradual dissipation of load and allows the package to conform toparticular shapes or products.

As mentioned, it is possible to have a single sealable entry port 14through which air can enter the package for inflating the cells. Thepackage can then be sealed at the entry point either using a valve, heatseal, adhesive, or an integral adhesive patch supplied with thecushioning apparatus adjacent the entry port. An integral adhesive patchis illustrated in FIG. 3. FIG. 3 shows the entry port 30 formed in anouter surface 33 of the apparatus for inflating the apparatus and apatch 31 sealed to the outer surface 33 at one side, forming a hinge 32adjacent the entry port 30. The patch is covered with adhesive on thesurface facing the entry port and the adhesive is covered with apeelable tab. In use; once inflated, the peelable tab is removed and thepatch pressed over the entry port to seal it. The tab can be attached toeither the upper or the lower sheet forming the apparatus.

Alternatively, a cushioning apparatus can be provided in which not allof the cells are in fluid communication with one another and so aplurality of air entry points are provided. With this arrangement,should one of the sealable entry points fail, resulting in deflation ofthe cells in fluid communication with that entry point, there remainsome cells that will remain fully inflated, providing some cushioning.

The cushioning apparatus can be supplied to customers in inflated formor ready for inflation by standard, table top inflation equipment.Clearly, supplying the apparatus non-inflated reduces the volume of theproduct and so reduces transportation costs.

As illustrated in FIG. 1b , with the arrangement of internal seals 13shown in FIG. 1a , the inflatable cells have substantially hemisphericaltop and bottom surfaces when filled or inflated. It is well known thathemispherical cells of this type support greater loads than other shapesand provide for excellent impact protection. The generally square shapedcells and cross shaped internal seals 13 gives rise to the hemisphericalprofile of the cells.

Numerous options for the arrangement of cells are possible with thepresent invention, including multilayer structures in which each layerof cells may or may not be in fluid communication with the next.However, it is envisaged that for most applications a single layer ofcushioning material will be sufficient.

When the cushioning apparatus is no longer required, the air or gas canbe removed from it by simply puncturing one of the cells, removing atear strip or opening the entry port. In a conventional bubble wrap thisis not possible because each of the cells is isolated from one another.

The cushioning apparatus can have an area of no inflatable cavities,which facilitates the cushion being folded over onto an article to beprotected. Such a construction can be fixed onto a corrugated boardsurface, cut and creased so that the construction wraps around fragilearticles. At the end of the product's life, segregation of materials isnot required, as the internal PVOH cushion is totally biodegradable asis the cardboard. In fact, PVOH is used in the re pulping process toenhance the recycling of paper and board. Existing compositeconstructions using board base packaging with internal polymericprotection, such as bubble wrap and profiled foam, require segregationbefore they can be recycled.

The size of the passages 15 connecting the inflatable cells can bechosen to suit a particular application. The narrower the passage 15,the more resistance is required for air or gas to pass from cell tocell. This, together with the amount of air or gas in the cushioningapparatus, affects the amount and type of cushioning provided by thepackage.

During trials using the general construction of the present invention, anumber of unexpected benefits have been noted. Unlike in polyethylenebased packaging cushions, the cells produced provide considerablenon-abrasive grip to the articles packed, perhaps due to the elongationproperties of PVOH film, which is known to have at least between five toseven greater times elongation, tensile strength and puncture resistancethan like for like products. Also, when filled with air, it appears thatthe PVOH film envelope construction has an affinity to itself whichretards air flow, resulting in more shock being dissipated that whenconstructed with other materials.

The present invention of making a fluid fillable multi-celled apparatusfrom a polyvinyl alcohol film teaches away from the current methods. Thevast majority of so called “bubble wrap” film is made by thermoforming.The finished product is made by heating the bottom web of film andsucking the film into the shapes required. In doing this, the drawncavities are inherently weaker due to thinning of the bottom sectionduring the thermoforming process. With the present invention nothermoforming process is required, and the film thickness will remainuniform throughout. Furthermore, in the case of adhesive seals with PVOHit is known that the seal integrity is greater than that of aconventional heat seal.

Accordingly, a cushioning apparatus in accordance with the presentinvention, in which there are a plurality of fluidly connectedinflatable cells, provides for a flexible cushioning apparatus that canbe made to conform through a particular article or product whilst at thesame time providing excellent cushioning properties, dissipating shockincident on a particular portion of the package through the entirecushioning apparatus.

A further aspect of the invention is the use of “sacrificial” seals inaddition to permanent seals to bond the first and second sheetstogether. Sacrificial seals are seals that are made to break at aparticular predetermined pressure, the predetermined pressure beinglower than the pressure at which the permanent seals rupture of thefirst and second sheets rupture. The use of sacrificial seals within theinterior of an inflatable cushioning apparatus provides for greatershock absorption. This is true of a PVOH cushioning apparatus inaccordance with the first aspect of the invention as well as forinflatable cushioning apparatus made using conventional materials, suchas polyethylene.

FIG. 4 illustrates a corner section of a cushioning apparatus of thetype shown in FIG. 1, incorporating sacrificial seals. A permanent seal12 is formed between two sheets around a periphery of the apparatus, asdescribed with reference to FIG. 1. The permanent seal can be formedusing adhesive, heat sealing or any other suitable method. Permanentinterior seals 13, defining interior cells, are also formed between theupper and lower sheet, as described with reference to FIG. 1. Inaddition a sacrificial seal or a series of sacrificial seals 40 areformed parallel to the peripheral seal 12. As shown, the sacrificialseals are 40 formed between permanent seals 42, but a single elongatesacrificial seal can be used instead. The sacrificial seals divide theinterior cells from holding chamber 41, so that in normal use theholding chamber 41 remains uninflated. However, if the internal pressurein the interior cells reaches a predetermined pressure due to anexternal load, at least one sacrificial seal will break, allowing air orgas from the interior cells into the holding chamber 41, thus reducingthe internal pressure and dissipating the load.

The sacrificial seal or seals can be formed using heat seals that areoptimised by altering the parameters of pressure, dwell time andhumidity. Alternatively or in addition, a peelable adhesive that peelsat a predetermined internal pressure may be used. One suitable adhesivefor forming peelable seals with PVOH film is the S100 adhesive,available from Sustainable Adhesive Products, Unit 3, Swangate, CharnhamPark, Hungerford, Berkshire, RG17 OYX, United Kingdom. The permanentseals can be formed using heats sealing or using adhesive.

With sacrificial seals as shown in FIG. 4, not only is the cushionfactor increased, but in comparison with conventional air filledpackaging, more protection is provided during transport in pressurisedholds found in aircraft. In such pressurised conditions conventional airfilled packaging described in the art can rupture resulting in loss ofcushioning. Sacrificial seals address this problem by allowing theexcess compression on the cushion to breach the sacrificial sealsallowing the excess air to escape into the holding reservoir.

FIG. 5 illustrates a further embodiment of a cushioning apparatus inaccordance with the present invention, using sacrificial seals. As inthe embodiment of FIG. 1, a permanent peripheral seal 12 is formedbetween an upper and a lower sheet. A plurality of permanent interiorseals 13 is also formed between the upper and lower sheet to define aplurality of cells. A plurality of sacrificial seals 50 is included,separating some cells from an adjacent cell. The sacrificial seals willrupture at a predetermined internal pressure, again providing fordissipation of shock.

With the arrangement of FIG. 5, plural input ports are required, in thiscase three, as not all of the cells are in fluid communication with eachother. In the apparatus shown in FIG. 5, three isolated rows of cellsare formed, separated by sacrificial seals, each row requiring inflationfrom a separate input port 14.

Each separate group of cells can be inflated to different degrees, (somemay not be inflated at all providing a holding chamber similar to thatillustrated in FIG. 4) allowing for variable cushioning and differentrates of diffusion of gas from one to the other when a sacrificial seal50 ruptures. The provision of separate groups of cells also ensures thatsome cushioning remains if one of the input ports 14 fails to seal orruptures during use.

A cushioning apparatus in accordance with the invention can be producedwith any number or pattern of cells. It may be produced pre-inflated,partially pre-inflated or not inflated at all. If not inflated, it canbe provided in roll form such that desired lengths of cushioningapparatus can be cut or torn from the roll. As mentioned the first andsecond layers may be laminated and may be formed of different materialto one another.

A cushioning apparatus in accordance with the present invention can beused in a number of applications, such as postal envelopes, for use asvoid fill packaging for shipping fragile goods, in protective clothingor any application in which protection from external load is required.

FIG. 6 is a flow diagram illustrating the steps in manufacturing anapparatus in accordance with preferred embodiment of the invention. Theprocess starts at step 600. The first sheet is formed at step 610. Thisis preferably a cast sheet of polyvinyl alcohol, formed from partly orfully hydrolysed polyvinyl acetate, as previously described. The secondsheet is formed at step 620. The second sheet is preferably a cast sheetof polyvinyl alcohol, formed from partly or fully hydrolysed polyvinylacetate, as previously described. However, either the first or thesecond sheet may be formed from a different material and either or bothmay be formed using a different method. At step 630, adhesive is printedonto the first sheet for forming permanent seals, including a peripheralseal. At step 640 adhesive for the non-permanent or “sacrificial” sealsis printed onto the first sheet. This may be done as a separate step tostep 630 or at the same time. The first and second sheets are thenpressed together at step 650 to form the seals. After the adhesive isset, the cushioning apparatus is complete and may, at step 660, berolled or folded ready for inflation on site, or may be pre-inflatedprior to shipping.

Another application of the present invention is in the production offluid or powder filled packages, particularly where water solubility ofthe package is required, as with detergents. FIG. 7 shows a packageuseful for forming individual fluid or powder filled packages. As withthe embodiment shown in FIG. 1, the package comprises two sheets ofpolyvinyl alcohol (PVOH) film bonded to one another to provide aplurality of fillable cells between them. As shown, upper sheet 70 isbonded to lower sheet (not shown) with a peripheral seal 72 around thecircumference of each sheet. The upper and lower sheet may be formedfrom a single web of PVOH, so that on one side, instead of a permanentseal, there is simply be a fold line. Further bonds 73 are made betweentop sheet 10 and bottom sheet 11 in an interior region to define aplurality of interconnected cells. An input port 74 is provided, in agap in the peripheral seal 72, in order to allow the cells to be filledwith fluid or powder. A desired volume of fluid, such as liquiddetergent, can be pumped into the package via input port 74. Input port74 can then be sealed to retain the fluid. Further seals 75, shown indotted line, can then be formed between the cells to isolate them fromone another, so that plurality of filled and sealed cells is formed. Thecells can then be separated from one another by cutting or tearing alongthe seals between the cells.

Although the embodiment of FIG. 7 uses a PVOH package, any suitablecombination of materials may be used in this method. PVOH has theadvantage that it is water soluble, but other materials may be suitablefor specific applications.

Another aspect of the invention is therefore a method for producing aplurality of fluid or powder filled packages, comprising the steps of:providing a first package comprising a first sheet bonded to a secondsheet to provide a plurality of interconnected fluid fillable chambersand an input port providing access to the chambers, filling the chamberswith a predetermined volume of the fluid or powder; and forming sealsbetween the chambers and the across the input port to provide aplurality of sealed fluid or powder filled chambers.

The use of an apparatus in accordance with the present invention in thisway provides a simpler and cheaper method to form individual dosedpackages of fluid or powder than current methods. Current methodsrequire thermoforming cavities and individual filling of the cavities.

The invention claimed is:
 1. A cushioning apparatus comprising first andsecond sheets bonded to one another, at least one of the first andsecond sheets being flexible, and configured to provide a plurality ofinflated chambers between the first and second sheets, wherein at leastone of the first and second flexible sheets is formed from polyvinylalcohol, wherein the first and second sheets are bonded to one anotherat a periphery using a permanent seal and are bonded to one another inat least one location within the periphery using a non-permanent seal,wherein the non-permanent seal is configured to rupture when an internalfluid pressure of the plurality of inflated chambers reaches apredetermined pressure due to an external load, and the predeterminedpressure being less than a pressure needed to rupture the permanent sealor the sheets.
 2. A cushioning apparatus according to claim 1, whereinat least one of the non-permanent seal and the permanent seal is formedusing an adhesive.
 3. A cushioning apparatus according to claim 1,wherein the first and second sheets are of substantially uniformthickness.
 4. A cushioning apparatus according to claim 1, wherein eachof the inflated chambers has a substantially hemispherical surface.
 5. Acushioning apparatus according to claim 1, wherein the first and secondflexible sheets have a thickness of between 40 and 70 microns.
 6. Acushioning apparatus according to claim 1, wherein at least one of thefirst and second flexible sheets is formed from cast polyvinyl alcohol.7. A cushioning apparatus according to claim 1, wherein at least some ofthe plurality of inflated chambers are interconnected such that they arein fluid communication with one another.
 8. A cushioning apparatuscomprising first and second sheets bonded to one another, at least oneof the first and second sheets being flexible, and configured to providea plurality of inflated chambers between the first and second sheets,wherein at least some of the plurality of inflated chambers areinterconnected such that they are in fluid communication with oneanother, further comprising at least one secondary chamber not in fluidcommunication with the plurality of interconnected chambers, wherein thefirst and second sheets are bonded to one another at a periphery using apermanent seal and are bonded to one another in at least one locationwithin the periphery using a non-permanent seal, wherein thenon-permanent seal is configured to rupture when an internal fluidpressure of the interconnected chambers reaches a predetermined pressuredue to an external load, and the predetermined pressure being less thana pressure needed to rupture the permanent seal or the sheets, whereinat least one of the non-permanent seal and the permanent seal is formedusing an adhesive.
 9. A cushioning apparatus according to claim 8,wherein the non-permanent seal is positioned between one of theinterconnected chambers and said at least one secondary chamber suchthat when the non-permanent seal is ruptured the one of theinterconnected chambers is in fluid communication with the at least onesecondary chamber.
 10. A cushioning apparatus according to claim 8,wherein the at least one secondary chamber is formed adjacent aperiphery of the apparatus.
 11. The cushioning apparatus of claim 8,wherein said at least one secondary chamber is uninflated or is inflatedto a different degree than the plurality of inflated chambers.
 12. Acushioning apparatus according to claim 8, wherein the first and secondsheets are of substantially uniform thickness.
 13. A cushioningapparatus according to claim 8, wherein each of the inflated chambershas a substantially hemispherical surface.
 14. A cushioning apparatusaccording to claim 8, wherein the first and second flexible sheets havea thickness of between 40 and 70 microns.
 15. A cushioning apparatusaccording to claim 8, wherein at least one of the first and secondflexible sheets is formed from polyvinyl alcohol.
 16. A cushioningapparatus comprising first and second sheets bonded to one another, atleast one of the first and second sheets being flexible, and configuredto provide a plurality of inflated chambers between the first and secondsheets, wherein at least one of the first and second flexible sheets isformed from polyvinyl alcohol, wherein at least some of the plurality ofinflated chambers are interconnected such that they are in fluidcommunication with one another, further comprising at least onesecondary chamber not in fluid communication with the plurality ofinterconnected chambers, wherein the first and second sheets are bondedto one another at a periphery using a permanent seal and are bonded toone another in at least one location within the periphery using anon-permanent seal, wherein the non-permanent seal is configured torupture when an internal fluid pressure of the interconnected chambersreaches a predetermined pressure due to an external load, thepredetermined pressure being less than a pressure needed to rupture thepermanent seal or the sheets, and wherein the nonpermanent seal ispositioned between one of the interconnected chambers and said at leastone secondary chamber such that when the non-permanent seal is rupturedthe one of the interconnected chambers is in fluid communication withthe at least one secondary chamber.
 17. A cushioning apparatus accordingto claim 16, wherein the at least one secondary chamber is formedadjacent a periphery of the apparatus.
 18. The cushioning apparatus ofclaim 16, wherein said at least one secondary chamber is uninflated oris inflated to a different degree than the plurality of inflatedchambers.
 19. A cushioning apparatus according to claim 16, wherein thefirst and second sheets are of substantially uniform thickness.